JP3410733B1 - Optical equipment - Google Patents

Abstract

To provide an optical device which can maintain optical performance, reduce the size of a lens barrel during non-photographing, and can directly mount accessories. SOLUTION: A first lens group L1 constituting an optical system is provided.
And a drive motor 17 for driving the first lens unit L1 using the main body 6 having the cam groove 6a formed thereon, and a second lens unit provided on the optical axis image plane side of the first lens unit L1 L2
And a drive motor 11 for driving the second lens unit L2
In response to the storage instruction of the optical system, the retraction of the first lens unit L1 is started after the retraction of the second lens unit L2, and the first lens unit is moved into the space made by the retraction of the second lens unit L2. And control means for controlling the driving motors 1 and 17 so as to carry out L1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical device using a lens barrel such as a video movie, which is excellent in portability, in which the length of the lens barrel is shortened when not photographing, compared to when photographing. is there.

[0002]

2. Description of the Related Art In recent years, along with the widespread use of digital video movies, miniaturization is desired. Therefore, an optical device using a so-called collapsible lens barrel is proposed in which the length of the lens barrel is shortened during non-shooting in consideration of portability during non-shooting as the lens barrel is downsized.

Conventionally, as a collapsible lens barrel for optical equipment, one described in the patent document is known. Figure 1
7 and 18 show the structure of a conventional retractable lens barrel.

In the figure, L1 is a first lens group which is fixed at the time of photographing (during zooming and focusing), and L2 is a second lens group for zooming.
A lens unit L3 is a third lens unit fixed at the time of shooting, and a lens unit L4 is a fourth lens unit that moves on the optical axis at the time of correction of image plane variation due to zooming and focusing. Reference numeral 31 is a fixed barrel that holds the image sensor FA in a fixed manner. 37 is a first holding frame,
It holds the first lens unit L1. Reference numeral 39 denotes a second holding frame, which holds the second lens unit L2, and the first holding frame 3
Bars 40 and 4 fixed between 7 and female helicoid 43
1 makes it possible to move in the optical axis direction. The female helicoid 43 is fixed to the first holding frame 37 and is coupled to the helicoid provided on the outer peripheral portion of the fixed barrel 31. Reference numeral 42 denotes a drive motor that drives the first lens group L1, that is, the first holding frame 37 in a straight line direction in the optical axis direction by engaging a gear 43a provided on the outer peripheral portion of the female helicoid 43 with an output gear 42a during non-photographing. I am letting you.

[0005]

[Patent document] Japanese Unexamined Patent Publication No. 8-179188

[0006]

However, the conventional retractable lens barrel optical apparatus has the following problems.

(1) When the first lens unit L1 is moved at the time of photographing, it is necessary to minimize the positional deviation with respect to the other lens units and reduce the adverse effect on the optical performance, but the first holding frame 37 is fixed. Due to the rattling of the cylinder 31, the optical deviation could not be minimized. Further, since the first holding frame 37 is guided to the outer peripheral surface of the fixed barrel 31, the size of the lens barrel becomes large, and the first lens group L1 is exposed to the outside even during non-shooting. I couldn't.

(2) When the first lens unit L1 is moved,
The first lens unit L1 projects from the optical device body. Therefore, when an external force is applied to the projecting portion, a force is applied to the lens itself and a positional shift occurs, so that basic optical performance cannot be maintained.

(3) Accessories such as a conversion lens and a filter cannot be directly attached to the protruding first lens unit L1.

Therefore, an object of the present invention is to provide a collapsible lens barrel which can maintain the optical performance, reduce the size of the lens barrel when not photographing, and directly mount an accessory. It is to provide an optical device using the.

[0011]

An optical device according to claim 1 drives the first lens group by using a first lens group which constitutes an optical system and a cam frame in which a cam groove is formed. A first driving unit, a second lens unit which is provided on the optical axis image plane side of the first lens unit and which constitutes the optical system, and a second driving unit which drives the second lens unit. When, in response to said storage instruction optics renormalization of the first lens group starts after renormalization the second lens group, the second
The control means for controlling the first drive means and the second drive means so as to retract the first lens group into the space vacated by the retraction of the lens group.

According to the optical device of the first aspect, it is possible to reduce adverse effects on the optical performance. In addition, the length of the lens barrel in the optical axis direction can be shortened at the time of non-photographing, the optical device can be downsized, and the portability can be improved. It is also possible to wear accessories directly.

[0013]

[0014]

According to a second aspect of the present invention, in the first aspect , the second driving means uses a motor having a feed screw. Therefore, claim 1
Has the same effect as.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, an optical apparatus using a retractable lens barrel of a proposed example which is the basis of the present invention will be described with reference to FIGS. 1 and 2.

L1 is a first lens group that is fixed during shooting, L2 is a second lens group for zooming, L3 is a third lens group that is fixed during shooting, and L4 is correction and focusing of image plane variation due to zooming. In this case, the fourth lens group moves along the optical axis.

Reference numeral 1 denotes a first holding frame, which is a first lens unit L1.
Holding One end of two guide poles (guide members) 7 is fixed to the first holding frame 1. Generally, in a lens barrel used for a video movie, the diameter of the first lens unit L1 is the largest. Therefore, by fixing one end of the guide pole 7 to the position of the outermost diameter of the first lens unit L1 or fixing it in the optical axis center direction from the position of the outermost diameter of the first lens unit L1, the outer diameter of the lens barrel which is increased by making the lens barrel retractable The increase can be minimized. 2 is the second lens unit L2
It is a second holding frame for holding and is movable by the two guide poles 7 in the optical axis direction. Further, the second holding frame 2 is moved in the optical axis direction by a driving force from the driving motor 11 via a feed screw (not shown) to perform zooming.
Reference numeral 3 denotes a fixed third holding frame for holding the third lens unit L3, which is sandwiched and fixed by the main body 6 and the master flange (fixed lens barrel) 5. A fourth holding frame 4 holds the fourth lens unit L4, and is movable in the optical axis direction by two guide poles 8 held between the third holding frame 3 and the master flange 5. Further, the fourth holding frame 4 is moved in the optical axis direction by a driving force from the driving motor 12 via a feed screw (not shown) to correct an image plane variation due to zooming and perform focusing. There is. An image sensor 13 is fixed to the master flange 5. Reference numeral 14 is a diaphragm unit.

A guide pole 7 is provided on the master flange 5.
Supports 9 and 10 for slidably supporting the lens are provided in parallel with the center of the optical axis. The support portion 9 is composed of two metal bearings 9a and 9b integrated with the master flange 5, and sufficient accuracy such as difference in inner diameter of these metal bearings 9a and 9b and coaxiality is ensured. Therefore, since the guide pole 7 slides on the two support portions 9 and 10, the first pole held by the first holding frame 1 to which one end of the guide pole 7 is fixed is held.
The optical axis center of the lens group L1 does not deviate from the optical axes of the fixed lens group L3 and the focusing lens group L4 and the center of the image sensor 13 even if the first holding frame 1 moves. Therefore, predetermined optical performance can be secured. The second holding frame 2 that moves during zooming also moves in the optical axis direction by the guide pole 7, so
Like the holding frame 1, it does not deviate from the optical axis.

Reference numeral 15 is a driving motor (driving means) for moving the first holding frame 1, and the feed screw 15a integrally provided via the reduction gear is attached to the projection 1a of the first holding frame 1. It meshes with the provided screw part. Therefore, the first holding frame 1 can be moved in the optical axis direction by the rotation of the drive motor 15.

The operation of the retractable lens barrel constructed as described above will be described below.

First, the operation of shifting from the shooting state shown in FIG. 1 to the non-shooting state shown in FIG. 2 will be described.

When the shooting preparation switch or the like is turned off from the shooting state shown in FIG. 1, the shooting ends. The second holding frame 2 is moved to the image plane side (direction of arrow A) by the drive motor 11. Next, the drive motor 15 rotates and the feed screw 15a rotates, so that the first holding frame 1 moves in the image plane direction. The sensor detects that the first holding frame 1 has moved to a predetermined position, and the rotation of the drive motor 15 stops. As a result, as shown in FIG. 2, the lens barrel is in a retracted state in which the length of the lens barrel in the optical axis direction is shortened by the distance b as compared with the case of FIG. Thus, the drive motor 11 and the drive motor 15 respond to the storage instruction of the optical system by the second lens group L.
After the second lens group L1 has been retracted, the first lens group L1 starts to retract, and the first lens group L1 is controlled to retract into the space vacated by the retraction of the second lens group L2.

Next, from the non-photographing state shown in FIG.
The operation at the time of shifting to the state at the time of shooting shown in will be described.

When the photographing preparation switch or the like is turned on from the non-photographing state of FIG. 2, the photographing preparation state is set. The drive motor 15 rotates and the feed screw 15a rotates, so that the first holding frame 1 moves to the object side (the direction opposite to the arrow A). The sensor detects that the first holding frame 1 has moved to a predetermined position, and the rotation of the drive motor 15 stops.
As a result, the first lens unit L1 shown in FIG. 1 is fixed at a predetermined position at the time of photographing. Here, the first holding frame 1 moves to a predetermined position, but the guide pole 7 slides on the supporting members 9 and 10 of the master flange 5 mounted with high precision, so that the guide pole 7 is fixed to the first holding frame 1.
The holding frame 1 also does not deviate from the center of the optical axis, and a predetermined optical performance can be secured. During actual shooting, drive motor 1
After the second holding frame 2 and the fourth holding frame 4 are moved to the initial positions by 1 and the driving motor 12, respectively, the zooming operation and the correction of the image plane variation accompanying the zooming and the focusing operation are started. . That is, in response to an instruction to extend the optical system, the first lens group L1 is extended, the extension of the second lens group L2 is started, and the second lens group L2 is extended to the space vacated by the extension of the first lens group L1. The drive motors 15 and 11 are controlled as described above.

As described above, according to this proposal, one end of at least two guide poles 7 is connected to the first lens unit L1.
Is fixed to the first holding frame 1 for holding, and the other end of the guide pole 7 is provided on the master flange 5 with supporting portions 9,
Since it is slidably supported, it is possible to minimize the optical shift when the first lens unit L1 is moved, and reduce the adverse effects on the optical performance. Further, by providing the guide pole 7 as described above while suppressing the increase in the outer diameter of the lens barrel which is increased by adopting the retractable type, the first holding frame 1 is provided with the optical axis of the master flange 5. The shape can be stored in the body 6 on the object side, and the length of the lens barrel in the optical axis direction at the time of non-shooting can be shortened, so that the optical device can be downsized and the portability can be improved. be able to.

In this proposed example, the movement of the first holding frame 1 in the optical axis direction is performed using the feed screw 15a, but other configurations such as a linear motor may be used. Further, it is also possible to use only two guide poles and move the fourth holding frame 4 as well as the second holding frame 2 in common. Alternatively, a configuration may be adopted in which a slide motor of a viewfinder provided in the optical device is used as a trigger to operate a drive motor that moves the first holding frame 1.

Further, in this proposal example, the optical system in which the first lens unit L1 is extended to the object side at the time of photographing and fixed and used at a predetermined position has been described. However, by changing the optical system, the first lens unit L1 is used. It is possible to use a variable length system in which the group L1 is used at an arbitrary position while moving, and the lens barrel length is changed according to the magnification of zooming.

Next, a first embodiment of the present invention will be described with reference to FIGS. FIG. 5 shows a state in which the outer frame 16 is taken out from the main body 6. The same components as those described above are designated by the same reference numerals and the description thereof will be omitted.

Reference numeral 16 denotes an outer frame provided outside the first holding frame 1, the outer periphery of which is slidable with the inner periphery of the main body 6. The outer frame 16 is for protecting the first holding frame 1 from being directly applied with force when the first holding frame 1 projects from an optical device or the like. On a part of the outer circumference of the outer frame 16,
As shown in FIG. 5, a plurality of cam shafts 16a are provided. Further, a gear 16b is formed in a portion where the cam shaft 16a is not provided. The gear 17 a of the drive motor 17 meshes with the gear 18 mounted on the main body 6, and the gear 18 meshes with the gear 16 b provided on the outer frame 16. That is, when the drive motor 17 rotates, the driving force is transmitted to the outer frame 16, and the outer frame 16 rotates at a constant speed around the optical axis.

A spiral cam groove 6a is formed in a part of the main body 6.
Is provided, and the cam shaft 16a provided on the outer frame 16 is engaged with the cam groove 6a. Further, the first holding frame 1 is rotatably engaged with the outer frame 16 about the optical axis by a part 1b thereof. Therefore, the outer frame 16 is rotationally moved in the optical axis direction along the cam groove 6a by the driving force of the driving motor 17. Since the guide pole 7 is supported by the supporting members 9 and 10 and is movable in the optical axis direction, the first holding frame 1 is also configured to move straight in the optical axis direction.

The operation of the retractable lens barrel constructed as above will be described below.

First, the operation of shifting from the shooting state shown in FIG. 3 to the non-shooting state shown in FIG. 4 will be described.

When the shooting preparation switch or the like is turned off from the shooting state shown in FIG. 3, the shooting ends. The second holding frame 2 is moved to the image plane side by the driving motor 11. Next, the drive motor 17 rotates, and the outer frame 16 moves in the image plane direction while rotating around the optical axis via the gear 18, so that the first holding frame 1 also moves in the image plane direction. The sensor detects that the first holding frame 1 has moved to a predetermined position, and the drive motor 17 stops rotating. As a result, as shown in FIG. 4, a retracted state in which the length of the lens barrel in the optical axis direction is shortened by the distance b as compared with the case of FIG.

Next, from the non-photographing state shown in FIG.
The operation at the time of shifting to the state at the time of shooting shown in will be described.

When the photographing preparation switch is turned on from the non-photographing state of FIG. 4, the photographing preparation state is set. The drive motor 17 rotates, and the outer frame 16 moves toward the object via the gear 18 while rotating around the optical axis, so that the first holding frame 1 also moves toward the object. The sensor detects that the first holding frame 1 has moved to a predetermined position, and the driving motor 1
The rotation of 7 stops. As a result, the first lens unit L1 shown in FIG. 3 is fixed at a predetermined position at the time of shooting.
Here, the first holding frame 1 moves to a predetermined position, but the guide pole 7 is accurately attached to the master flange 5.
By sliding the supporting members 9 and 10 of the above, the first holding frame 1 to which the guide pole 7 is fixed does not deviate from the center of the optical axis, and a predetermined optical performance can be secured. Further, the outer frame 16 protruding at the same time as the first holding frame 1 is directly connected to the first holding frame 1
It serves to protect external forces from being applied to them. At the time of actual photographing, after the second holding frame 2 and the fourth holding frame 4 are moved to the initial positions by the driving motor 11 and the driving motor 12, respectively, the zooming and the correction of the image plane variation due to the zooming are respectively performed. And the focusing operation is started.

As described above, according to this embodiment, the increase in the outer diameter of the existing lens barrel which is not the collapsible type is minimized as in the case of the proposed example, and the light of the lens barrel is used during non-photographing. Since the length in the axial direction can be shortened, the optical device can be downsized and the portability can be improved. Moreover, it is possible to minimize the deviation of the optical axis when the lens is moved during shooting, and reduce adverse effects on the optical performance. In addition, the outer frame 1 for protecting the lens is provided outside the first holding frame 1.
By providing 6, the external force can be prevented from being directly applied to the lens, and the reliability of the lens barrel at the time of photographing can be improved.

In this embodiment, the outer frame 16 is moved in the optical axis direction by using the cylindrical cam in which the cam shaft 16a and the cam groove 6a are engaged with each other, but other configurations may be used. Alternatively, the drive motor for moving the outer frame 16 may be operated by using the slide operation of the viewfinder provided in the optical device as a trigger.

In this embodiment, the optical system in which the first lens unit L1 is extended to the object side and fixed at a predetermined position for use during photographing is described. However, the first lens unit L1 is changed by changing the optical system. It is possible to use a variable length system in which the group L1 is used at an arbitrary position while moving, and the lens barrel length is changed according to the magnification of zooming.

Next, a second embodiment of the present invention will be described with reference to FIG. Since the first embodiment is used, the same components as those described so far are designated by the same reference numerals and the description thereof will be omitted.

Reference numeral 16c is a screw for attaching accessories such as a conversion lens and a filter shown in 19 and is provided at the tip portion of the outer frame 16. Although the accessory mounting is indispensable for increasing the expandability of the optical device, it cannot be mounted on the fixed portion of the lens barrel because the first holding frame 1 projects toward the object side during photographing. Further, the first holding frame 1 cannot be attached directly because the positional accuracy cannot be maintained due to an external force at the time of attachment and an optical axis shift occurs. Therefore, the outer frame 1 for lens protection
Attach to 6.

The operation of the retractable lens barrel constructed as above will be described below.

The drive motor 17 rotates from a state (not shown) at the time of non-photographing, and the outer frame 16 moves toward the object while rotating around the optical axis via the gear 18 to move the first direction.
The holding frame 1 also moves in the object direction. The sensor detects that the first holding frame 1 has moved to a predetermined position, and the drive motor 17 stops rotating. As a result, the first lens unit L1 shown in FIG. 6 is in a state at the time of shooting with being fixed at a predetermined position. In this state, the accessory 19 can be easily attached by attaching the accessory 19 to the attachment screw portion 16c of the outer frame 16.

As described above, according to this embodiment, it is possible to mount the accessory, which has been difficult with the retractable lens barrel, by simply projecting the outer frame 16 by the same amount as the first holding frame 1. Can be realized. As a result, even an ultra-compact optical device having excellent portability can be provided with various expandability like the conventional optical devices.

Next, a third embodiment of the present invention will be described with reference to FIGS. 7 and 8. Since the configuration of the present invention is the same as that described in the first embodiment except for the portion that moves the focusing lens in the optical axis direction, the same reference numerals are given and the description thereof is omitted. .

Reference numeral 4 denotes a fourth holding frame for holding the fourth lens unit L4 for correcting and focusing the image plane variation due to zooming, around which the coil 23 is wound. The fourth holding frame 4 is movable in the optical axis direction by a guide pole (not shown) fixed between the third holding frame 3 and the master flange 5. At the rear of the master flange 5, a yoke 24 that is bent into a substantially U shape is provided.
A magnet 25 is provided on the yoke 24 to form a magnetic field. That is, the coil 23, the yoke 24, the magnet 25, and the guide pole constitute the linear motor 26. With this linear motor 26, the fourth holding frame 4
Can be moved in the optical axis direction. Reference numeral 27 denotes a pressing member attached to the rear of the guide pole 7, and when the guide pole 7 slides in the optical axis image plane direction, a fourth member is provided.
It is possible to press the holding frame 4.

The operation of the retractable lens barrel constructed as described above will be described below.

First, the operation for shifting from the shooting state shown in FIG. 7 to the non-shooting state shown in FIG. 8 will be described.

When the photographing preparation switch or the like is turned off from the photographing state shown in FIG. 7, the photographing is terminated. The second holding frame 2 is moved to the image plane side by the driving motor 11. Then, the drive motor 17 rotates, and the outer frame 16 moves in the image plane direction while rotating around the optical axis via the gear 18,
The first holding frame 1 also moves in the image plane direction. The sensor detects that the first holding frame 1 has moved to a predetermined position, and the drive motor 17 stops rotating. As a result, as shown in FIG. 8, a retracted state in which the length of the lens barrel in the optical axis direction is shortened by the distance b as compared with the case of FIG. Further, when the power is turned off, no current flows in the coil 23 of the linear motor 26 that drives the fourth holding frame 4, so the position of the linear motor 26 cannot be controlled and the fourth holding frame 4 cannot be held at a predetermined position. . Therefore, if external vibration or shock is applied,
A rattling sound is generated by the movement of the holding frame 4. Therefore, when retracted, the fourth holding frame 4 can be locked by pressing with the pressing member 27 provided behind the guide pole 7.

Next, from the non-photographing state shown in FIG.
The operation at the time of shifting to the state at the time of shooting shown in will be described.

When the photographing preparation switch is turned on from the non-photographing state of FIG. 8, the photographing preparation state is set. The drive motor 17 rotates, and the outer frame 16 moves toward the object via the gear 18 while rotating around the optical axis, so that the first holding frame 1 also moves toward the object. The sensor detects that the first holding frame 1 has moved to a predetermined position, and the driving motor 1
The rotation of 7 stops. As a result, the first lens unit L1 shown in FIG. 7 is in a state at the time of shooting with being fixed at a predetermined position.
Further, since the pressing member 27 also moves toward the object due to the movement of the guide pole 7, the lock of the fourth holding frame 4 is also released. At the time of actual photographing, after the second holding frame 2 and the fourth holding frame 4 are moved to the initial positions by the driving motor 11 and the linear motor 26, respectively, the zooming and the correction of the image plane variation accompanying the zooming are performed. Focusing operation starts.

As described above, according to this embodiment, even if the lens barrel uses the linear motor 26, which is excellent in terms of speeding up and low power consumption, it is possible to reduce the current by a simple structure by collapsing operation. The fourth holding frame 4 when not energized can be locked to prevent the generation of noise due to movement. That is, in the method of moving the fourth holding frame 4 of the fourth lens unit L4 that corrects and focuses the image plane variation due to zooming by the linear motor 26, a current is supplied to the coil 23 of the linear motor 26 when the power is turned off. Since the fourth holding frame 4 cannot be held at a predetermined position because it does not flow, the fourth holding frame 4 is configured to be fixed to the master flange 5 by the collapsing operation during non-shooting. 4 The rattling of the holding frame 4 can be prevented. Therefore, the reliability of the lens barrel can be improved.

Similarly, the second lens unit L for zooming is also used.
Even with a lens barrel that adopts a method of moving the second holding frame 2 of No. 2 by a linear motor, the second holding frame 2 when current is not supplied is locked by a simple structure by a collapsing operation, and noise caused by the movement is generated. Occurrence can be prevented.

Next, a fourth embodiment of the present invention will be described with reference to FIGS. The same components as those described above are designated by the same reference numerals and the description thereof will be omitted.

Reference numeral 1 denotes a first holding frame, which is a first lens unit L1.
Holding The first holding frame 1 is held by a guide pole 20 fixed to the main body 6 and the third holding frame 3 so as to be movable in the optical axis direction. Further, a cam shaft 1c is provided on one side of the first holding frame 1. A second holding frame 2 holds the second lens unit L2, and like the first holding frame 1, is held by two guide poles 20 so as to be movable in the optical axis direction. And second
A cam shaft 2a is provided on one side of the holding frame.
Reference numeral 21 is a cam cylinder having a circular cross section having cam grooves 21a and 21b, and the outer circumference of the cam cylinder can slide around the inner circumference of the main body 6 to rotate about the optical axis.

Here, FIG. 11 shows the shape of the cam barrel 21. Reference numeral 21a is a cam groove on which the cam shaft 1c of the first holding frame 1 slides, and 21b is a cam groove on which the cam shaft 2a of the second holding frame 2 slides. In the cam groove 21a, the cam shaft 21c advances in the direction of arrow D as the cam barrel 21 rotates in the direction of arrow B. The first holding frame 1 moves in the optical axis direction by the distance d due to the movement of the cam shaft 1c, but when the position M is exceeded, the cam groove 21a is orthogonal to the optical axis, so that the first holding frame 1 does not move further in the optical axis direction. . That is, this position is the predetermined position of the first holding frame 1 at the time of shooting. In the cam groove 21b, the cam barrel 21 makes a constant rotation in the direction of arrow B, but since it is initially orthogonal to the optical axis, the second holding frame 2 does not move in the optical axis direction until the position N is reached.
After that, when N is exceeded, it becomes possible to move by the distance e. That is, this distance e is the range of magnification change. A gear 21c is provided on a part of the cam barrel 21 and meshes with a gear 22a of the drive motor 22.

The operation of the retractable lens barrel constructed as described above will be described below.

First, from the state at the time of photographing shown in FIG. 9 to FIG.
The operation when shifting to the non-photographing state shown in FIG.

When the shooting preparation switch or the like is turned off from the shooting state shown in FIG. 9, the shooting ends. Drive motor 2
2 rotates and the cam barrel 21 rotates in the direction of arrow C, so that the cam shaft 2a slides along the cam groove 21b and moves to the position N on the most image plane side in the variable power range.
That is, the second holding frame 2 has moved to the most image plane side, and it does not move further in the optical axis direction. Further cam barrel 2
When 1 rotates, the camshaft 1c goes over the position of M,
The first holding frame 1 moves in the image plane direction. Then, the sensor detects that the first holding frame 1 has moved by the distance d and has reached a predetermined position, and the rotation of the drive motor 22 is stopped. As a result, as shown in FIG. 10, the lens barrel is in a retracted state in which the length of the lens barrel in the optical axis direction is shorter by the distance c than in the case of FIG.

Next, the operation for shifting from the non-shooting state shown in FIG. 10 to the shooting state shown in FIG. 9 will be described.

When the photographing preparation switch is turned on from the non-photographing state of FIG. 10, the photographing preparation state is set. When the drive motor 22 rotates and the cam barrel 21 rotates in the direction of arrow B, the cam shaft 1c slides along the cam groove 21a, and the first holding frame 1 moves a distance d in the optical axis object direction. To do. Even if the cam barrel 21 is further rotated, the first holding frame 1 does not move in the optical axis direction, so the first holding frame 1 is fixed at this position. That is, this state is the state at the start of shooting. At the time of actual photographing, the drive motor 22 further rotates to rotate the inside of the variable power range e in the forward and reverse directions to perform the variable power operation. At the same time, the fourth holding frame 4 is driven by the drive motor 12 to perform correction of the image plane variation due to zooming and focus operation.

As described above, according to this embodiment, the length of the lens barrel in the optical axis direction can be shortened at the time of non-photographing, so that the optical device can be downsized and the portability can be improved. You can Moreover, it is possible to minimize the deviation of the optical axis when the lens is moved during shooting, and reduce adverse effects on the optical performance. That is, since the guide pole 20 guides the movement of the first holding frame 1 and the second holding frame 2 in the optical axis direction, it is possible to minimize the optical shift when the first lens unit L1 moves, and to reduce the optical performance. The adverse effect can be reduced. Along with this, the shape of the first holding frame 1 can be reduced, and the first holding frame 1 and the second holding frame 2 are moved to the image plane side of the optical axis and housed in the main body 6 during non-shooting. Can be miniaturized. Further, the cam grooves 21a, 2 with which the first holding frame 1 and the second holding frame 2 engage with each other.
A cam cylinder 21 having a circular cross section having 1b is arranged on the main body 6 so as to be rotatable about the optical axis, and the cam cylinder 21 is rotated by a rotating means, whereby the collapsing operation of the first holding frame 1 and the first lens of the zoom lens. Since the two holding frames 2 can be moved by one drive motor 22, the cost can be reduced.

Next, a fifth embodiment of the present invention will be described with reference to FIGS. 12 to 15. The optical apparatus of the present invention uses the retractable lens barrel described in the proposed example, but the exterior of this embodiment can also be applied to the fourth embodiment. Therefore,
The same numbers are given to those described in the proposal example , and the description thereof will be omitted.

Reference numeral 50 is an optical device such as a video movie. 28 is an optical device 50 for mounting the retractable lens barrel.
Is a first exterior provided on the. 29 is the first exterior 28
On the other hand, it is the second exterior 29 that is movable in the optical axis direction.
The second exterior 29 can be moved by substantially the same amount as the amount of movement of the first holding frame 1 of the retractable lens barrel. Further, a manual button 29 a that allows the second exterior 29 to be moved by a manual operation is attached to the second exterior 29 in a state of protruding from the first exterior 28.

The operation of the optical device constructed as above will be described below.

First, from the state at the time of photographing shown in FIG.
The operation when shifting to the non-photographing state shown in 3 will be described.

When the photographing preparation switch or the like is turned off from the photographing state shown in FIG. 12, the photographing is completed. Second holding frame 2
Is moved to the image plane side by the drive motor 11. Then, the driving motor 15 rotates and the feed screw 15a rotates, so that the first holding frame 1 moves in the image plane direction. The sensor detects that the first holding frame 1 has moved to a predetermined position, and the rotation of the drive motor 15 stops. As a result,
As shown in FIG. 3, the lens barrel is in a retracted state in which the length in the optical axis direction is shorter by the distance b than in the case of FIG. Then, the operation is completed by moving the second exterior 29 to the image plane side with the manual button 29a.

Next, the operation for shifting from the non-shooting state shown in FIG. 13 to the shooting state shown in FIG. 12 will be described.

In the non-photographing state of FIG. 13, the second exterior 29 is moved to the object side by the manual button 29a, and when it is detected that it has moved to a predetermined position, the photographing preparation state is set. The drive motor 15 rotates and the feed screw 15a rotates, so that the first holding frame 1 moves to the object side. The sensor detects that the first holding frame 1 has moved to a predetermined position, and the rotation of the drive motor 15 stops. As a result, the first lens unit L1 shown in FIG. 12 is in a state at the time of shooting with being fixed at a predetermined position. At the time of actual photographing, after the second holding frame 2 and the fourth holding frame 4 are moved to the initial positions by the driving motor 11 and the driving motor 12, respectively, the zooming and the correction of the image plane variation due to the zooming are respectively performed. And the focusing operation is started.

As described above, according to this embodiment, it is needless to say that the length of the lens barrel in the optical axis direction at the time of non-shooting can be shortened to improve the portability of optical equipment such as a video movie. By making the exterior of the device slidable, the protruding first holding frame 1 can be protected,
The reliability of the optical device at the time of shooting can be improved.

In this embodiment, the driving motor 15 is driven by turning off the photographing preparation switch, but the driving operation is triggered by the movement of the second exterior 29 in the image plane direction. The motor 15 may be driven.

Further, the second outer casing 29 is a conventional optical device which is replaced with an opening / closing shutter provided on the front surface of the lens barrel, and in conjunction with the operation of feeding and storing the second outer casing 29, The configuration may be such that the opening / closing shutter provided in the optical device is operated.

Further, the sliding movement of the exterior may be configured to be interlocked with the sliding movement of the viewfinder. That is, the viewfinder and the exterior are mechanically slid in opposite directions. At the time of shooting, the viewfinder is extended backwards, and this rearward movement causes the exterior to be extended forwards. On the contrary, since the viewfinder is stored in the front during non-shooting, the exterior is stored in the rear by this forward movement.

Finally, a sixth embodiment of the present invention will be described with reference to FIG. Since the fifth embodiment is used, the same parts as those described so far are designated by the same reference numerals, and the description thereof will be omitted.

Reference numeral 29b is a screw for mounting accessories such as a conversion lens and a filter shown at 30, which is provided at the tip of the second exterior 29 of the optical device 50. Although the accessory mounting is indispensable for increasing the expandability of the optical device, it cannot be mounted on the fixed portion of the lens barrel because the first holding frame 1 projects toward the object side during photographing. In addition, the first holding frame 1 cannot be directly attached to the first holding frame 1 because the positional accuracy cannot be maintained due to an external force at the time of mounting and an optical axis shift occurs. Then, it is attached to the second exterior 29 for lens protection.

The operation of the optical apparatus constructed as above will be described below.

The second armor 29 is moved to the object side by the manual button 29a from the state (not shown) at the time of non-shooting, and when it is detected that it has moved to the predetermined position, the shooting ready state is set. The drive motor 15 rotates and the feed screw 15a rotates, so that the first holding frame 1 moves to the object side. The sensor detects that the first holding frame 1 has moved to a predetermined position, and the rotation of the drive motor 15 stops. As a result, the first lens unit L1 shown in FIG. 16 is in a state at the time of shooting with being fixed at a predetermined position. In this state, accessory 3
By attaching 0 to the mounting screw portion 29b of the second exterior 29, the accessory can be easily mounted.

As described above, according to this embodiment, it is difficult to mount an accessory on the exterior by the same amount as the first holding frame 1 when it is difficult to mount an accessory on an optical device such as a video movie using a retractable lens barrel. It can be realized by a simple configuration of performing. As a result, even an ultra-compact optical device having excellent portability can be provided with various expandability like the conventional optical devices.

[0079]

According to the optical device of the first aspect, it is possible to reduce adverse effects on the optical performance. In addition, the length of the lens barrel in the optical axis direction can be shortened at the time of non-photographing, the optical device can be downsized, and the portability can be improved. Further, by using the first lens group at an arbitrary position while moving it, it is possible to obtain a remarkable effect that it is possible to cope with a variable length system in which the lens barrel length changes depending on the magnification of zooming. It is also possible to wear accessories directly.

According to the optical apparatus of claim 2,
It has the same effect as 1.

[0081]

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part at the time of shooting according to a proposed example that is a basis of the present invention.

FIG. 2 is a cross-sectional view of a main part during non-shooting according to a proposed example.

FIG. 3 is a cross-sectional view of essential parts at the time of shooting according to the first embodiment of the present invention.

FIG. 4 is a cross-sectional view of a main part at the time of non-imaging according to the first embodiment.

FIG. 5 is a partially exploded perspective view of the first embodiment.

FIG. 6 is a cross-sectional view of essential parts when an accessory is attached according to a second embodiment of the present invention.

FIG. 7 is a cross-sectional view of essential parts at the time of shooting according to a third embodiment of the present invention.

FIG. 8 is a cross-sectional view of an essential part at the time of non-imaging according to the third embodiment.

FIG. 9 is a cross-sectional view of essential parts at the time of shooting according to a fourth embodiment of the present invention.

FIG. 10 is a cross-sectional view of an essential part at the time of non-imaging according to the fourth embodiment.

FIG. 11 is a schematic view of the shape of the cam groove of the cam barrel according to the fourth embodiment.

FIG. 12 is a cross-sectional view of essential parts at the time of shooting according to a fifth embodiment of the present invention.

FIG. 13 is a cross-sectional view of an essential part at the time of non-imaging according to the fifth embodiment.

FIG. 14 is a schematic view of an optical device at the time of shooting according to the fifth embodiment.

FIG. 15 is a schematic view of an optical device at the time of non-shooting according to the fifth embodiment.

FIG. 16 is a cross-sectional view of essential parts when an accessory is attached according to a sixth embodiment of the present invention.

FIG. 17 is a cross-sectional view of essential parts at the time of shooting with a conventional retractable lens barrel.

FIG. 18 is a cross-sectional view of a main part of the conventional retractable lens barrel during non-shooting.

[Explanation of symbols]

L1 first lens group L2 second lens group L3 Third lens group L4 4th lens group 1 first holding frame 2 Second holding frame 3rd holding frame 4th holding frame 5 master flange 6 body 6a Cam groove 7 Guide pole 9,10 Support member 11,15,17,22 Drive motor 16 outer frame 16a camshaft 21 cam barrel 50 Optical equipment

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-10-153729 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G02B ⁷ /02-7/16 G03B 17 / 04

Claims (2)

(57) [Claims] 1. A first lens group that constitutes an optical system, a first drive unit that drives the first lens group using a cam frame in which a cam groove is formed, and the first lens group. the optical provided in the optical axis image surface side
A second lens group constituting the system, the second drive means for driving the second lens group, in response to receiving an instruction of said optical system the first after renormalization the second lens group Start the retraction of the lens group,
An optical apparatus comprising: a control unit that controls the first drive unit and the second drive unit so that the first lens unit is retracted into a space vacated by the retraction of the second lens unit. 2. The second drive means is a model having a lead screw.
An optical machine according to claim 1, characterized in that
vessel.